U.S. patent application number 14/375089 was filed with the patent office on 2015-03-05 for placental blood extraction device.
The applicant listed for this patent is SG MediTech Pte Ltd.. Invention is credited to Saey Tuan Barnabas Ho, Mari Krizia Ong Leal, Gabriel Tan, Tiong Han Toh, Ron Wright.
Application Number | 20150065918 14/375089 |
Document ID | / |
Family ID | 48873739 |
Filed Date | 2015-03-05 |
United States Patent
Application |
20150065918 |
Kind Code |
A1 |
Toh; Tiong Han ; et
al. |
March 5, 2015 |
PLACENTAL BLOOD EXTRACTION DEVICE
Abstract
A placental blood extraction device comprises a receptacle for
receiving a placenta with umbilical cord, the receptacle comprising
a compartment arranged to receive the placenta; and a tube
extending from the compartment for receiving the umbilical cord;
wherein the receptacle is selectively removable from the device for
receiving the placenta. The placental blood extraction device may
comprise a pressure application device for applying pressure to a
placenta, the pressure application device comprising a plurality of
pressing members for applying pressure on a plurality of regions of
the placenta.
Inventors: |
Toh; Tiong Han; (Singapore,
SG) ; Wright; Ron; (Singapore, SG) ; Tan;
Gabriel; (Singapore, SG) ; Ho; Saey Tuan
Barnabas; (Singapore, SG) ; Leal; Mari Krizia
Ong; (Singapore, SG) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SG MediTech Pte Ltd. |
Singapore |
|
SG |
|
|
Family ID: |
48873739 |
Appl. No.: |
14/375089 |
Filed: |
January 28, 2013 |
PCT Filed: |
January 28, 2013 |
PCT NO: |
PCT/SG2013/000035 |
371 Date: |
July 28, 2014 |
Current U.S.
Class: |
600/581 ;
600/573; 600/584 |
Current CPC
Class: |
A61B 5/150076 20130101;
A61B 5/15003 20130101; A61B 5/150358 20130101; A61B 5/150366
20130101; A61B 5/150389 20130101; A61B 5/150083 20130101; A61B
5/150068 20130101; A61B 5/150045 20130101; A61B 5/157 20130101;
A61B 5/150229 20130101; A61B 5/150038 20130101; A61B 5/150992
20130101; A61B 5/150099 20130101; A61B 5/150755 20130101 |
Class at
Publication: |
600/581 ;
600/573; 600/584 |
International
Class: |
A61B 5/15 20060101
A61B005/15; A61B 5/157 20060101 A61B005/157 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 27, 2012 |
SG |
201200701-9 |
Claims
1. A placental blood extraction device comprising: a receptacle for
receiving a placenta with umbilical cord, the receptacle comprising
a compartment arranged to receive the placenta; and a tube
extending from the compartment for receiving the umbilical cord;
wherein the receptacle is selectively removable from the device for
receiving the placenta.
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. A placental blood extraction device comprising: a pressure
application device for applying pressure to a placenta, the
pressure application device comprising a plurality of pressing
members for applying pressure on a plurality of regions of the
placenta.
9. (canceled)
10. (canceled)
11. (canceled)
12. (canceled)
13. (canceled)
14. (canceled)
15. (canceled)
16. (canceled)
17. (canceled)
18. (canceled)
19. (canceled)
20. (canceled)
21. (canceled)
22. (canceled)
23. (canceled)
24. (canceled)
25. (canceled)
26. (canceled)
27. (canceled)
28. (canceled)
29. (canceled)
30. (canceled)
31. (canceled)
32. (canceled)
33. (canceled)
34. (canceled)
35. (canceled)
36. (canceled)
37. (canceled)
38. (canceled)
39. A cannula assembly comprising: a catheter; a housing mounted to
a portion of said catheter such that a length of catheter projects
from said housing; an introducer in sliding engagement with said
housing and arranged coaxially with said catheter wherein the
introducer is movable from an extended position having a
penetration end contiguous with an end of said catheter and a
retracted position such that said catheter end projects from said
penetration end.
40. The cannula assembly according to claim 39, further including a
selectively releasable lock arranged to lock the introducer in the
retracted position.
41. The cannula assembly according to claim 39 or 40, wherein the
introducer is a concentric sleeve positioned externally to the
catheter.
42. The cannula assembly according to claim 39, wherein the
retracted position places the introducer fully retractable within
the housing.
43. The cannula assembly according to claim 39, wherein the
assembly is arranged for penetrating a vein of an umbilical cord,
said catheter having a diameter equal to a diameter of the cord
vein.
44. A blood bag assembly comprising: a blood transfer conduit; a
blood bag coupled at a first end of said conduit; a cannula coupled
at an opposed end of said conduit; a blood sampling site for
obtaining a blood sample coupled at a position intermediate said
ends; a tapping for an perfusion system coupled at a position
intermediate said ends.
45. (canceled)
46. (canceled)
47. (canceled)
48. (canceled)
49. (canceled)
50. The cannula assembly according to claim 39, further including a
slide arranged to single handedly project said introduced from the
housing.
51. The cannula assembly according to claim 39, wherein the
catheter of the cannula assembly is soft and flexible.
52. The cannula assembly according to claim 51, wherein the
flexible catheter is arranged to expand the vein.
53. The cannula assembly according to claim 52, wherein the
flexible catheter is arranged to engage with the expanded vein to
reduce slipping between the vein and catheter.
54. The cannula assembly according to claim 52, wherein the
flexible catheter is arranged to engage with the expanded vein to
such that a diameter of the catheter is equal to a diameter of the
cord vein.
55. The cannula assembly according to claim 39, further including a
blood bag assembly coupled to said catheter with a conduit
intermediate the blood bag assembly and the catheter.
56. The cannula assembly according to claim 55, wherein the blood
bag assembly includes a 3 way junction, for controllable fluid
pathways amongst the 3 ports on the junction; one of said ports
including: a blood sampling site for obtaining a blood sample
coupled at a position intermediate said ends; a tapping for an
perfusion system coupled at a position intermediate said ends. a
syringe port coupled at a position intermediate said ends; a port
arranged to apply negative pressure to the cannula coupled at a
position intermediate said ends.
57. The cannula assembly according to claim 55 or 56, wherein the
blood bag assembly includes a perfusion system coupled to the
perfusate tapping.
58. The cannula assembly according to claim 57, wherein the
perfusion system includes a perfusate bag.
59. The cannula assembly according to claim 57 or 58, wherein the
perfusion system includes a tapping for a peristaltic pump.
60. The cannula assembly according to claim 57, wherein the
perfusion system includes a warming device for warming the
perfusate bag and/or the conduit used to transfer the
perfusate.
61. The cannula assembly according to claim 57, wherein the
retractable introducer concentrically and externally placed about
the catheter permits application of the cannula assembly to the
placenta in-utero.
Description
FIELD OF TECHNOLOGY
[0001] The present invention relates to a device and method for
extracting and/or collecting placental blood.
BACKGROUND
[0002] It is well known that umbilical cord blood (UCB) is an
increasingly important and rich source of stem cells. It is known
that stem cells can divide to create new red blood cells which
carry oxygen to the brain, new white blood cells used in the body's
immune system and new platelets which can assist in blood clotting.
It is currently estimated that stem cells may be used for the
treatment of over 45 malignant and non-malignant diseases. Such
diseases may include certain cancers such as leukaemia, immune and
genetic disorders.
[0003] UCB may also provide a readily available source of stem
cells for transplantation in many situations where bone marrow is
currently used. Hence, the use of UCB instead of other sources of
stem cells such as for example bone marrow and peripheral blood has
many advantages. Such may include for example the reduction or
elimination of risk involved in the collection of UCB.
[0004] UCB is also easier to collect and harvest while avoiding the
risks associated with general anesthesia, which is required for the
purposes of extracting bone marrow. UCB is also readily available
when needed, assuming an efficient and systematic collection and
storage procedure. It has been found that UCB is also more often
compatible with people undergoing transplants. Furthermore UCB has
a lower procurement cost. It has also been demonstrated that UCB
has broader potential clinical applications for improving neural
repair, bone and tissue growth.
[0005] As such, the importance of UCB is now widely recognized.
Blood centres worldwide may collect and store UCB after delivery of
a baby subject to the parents' consent or request.
[0006] However, a problem associated with UCB is that its
collection appears to be a one time possibility and the amount of
blood that can be collected is limited using current blood
collection technology. Such current blood collection technology may
include syringe assisted and gravity assisted methods.
[0007] A conventional placental blood extraction device include a
chamber for receiving a placenta and pressure application mechanism
for applying a pressure to the surface of the placenta to assist
extracting as much placental blood as possible.
[0008] However, it has been particularly cumbersome to place a
placenta properly into the chamber, and particular caution must be
taken to prevent the device from being contaminated by the placenta
before a second one is placed into the device. Cross contamination
between placentas must also be avoided. A known method of
preventing contamination is to provide a disposable membrane around
the internal surface of the chamber before placing the
placenta.
[0009] Further, the device needs to be sterilized between two
successive extraction processes. This takes more time and manpower
to prepare the device after a first extraction process and before a
second extraction and collection process.
SUMMARY OF INVENTION
[0010] In a first aspect, the invention provides a placental blood
extraction device comprising a receptacle for receiving a placenta
with umbilical cord, the receptacle comprising a compartment
arranged to receive the placenta; and a tube extending from the
compartment for receiving the umbilical cord; wherein the
receptacle is selectively removable from the device for receiving
the placenta.
[0011] This allows a user to enclose the placenta in a disposable
receptacle so as to allow the extraction of cord blood while
avoiding direct exposure of biological tissue to the pressure
applicator. This facilitates the operation of the device because
only minimal sterilization procedures, or no sterilization
procedures, are required to ready the device for the next set of
cord blood collection.
[0012] The placental blood extraction device may further include a
frame having wheels said frame having a bracket for suspending the
receptacle.
[0013] The placental blood extraction device may further include a
perfusion system mounted to said frame, said perfusion system
including an perfusate bag and a peristaltic pump for pumping
perfusate into the placenta. The perfusion system may include a
warming device for warming the perfusate bag. The perfusion system
may include a warming device for warming blood in the conduit for
transferring the perfusant.
[0014] The placental blood extraction device may further include a
bracket for supporting a blood bag for receiving extracted blood.
The blood bag bracket may include a rocking mechanism for rocking
the bracket. The blood bag may include sensors for detecting the
volume of blood in said bag. The sensor may be a load cell for
measuring the weight of the bag.
[0015] In a second aspect, the invention provides a placental blood
extraction device comprising a pressure application device for
applying pressure to a placenta, the pressure application device
comprising a plurality of pressing members for applying pressure on
a plurality of regions of the placenta.
[0016] The device allows application of spatially differential
pressure on the placenta to achieve a high efficacy. A uniform or
centrically high pressure would hamper the drainage of blood from
the placenta to the umbilical cord. This can be averted by a
gradual build up of pressure from the periphery of the placenta to
the centre where the umbilical cord is attached.
[0017] An advantage that may become available as a result of the
invention is the ability to drive blood from the periphery of the
placenta to the "centre" so as to be extracted from the cord.
Whilst centrally located blood is easily extractable, in order to
maximize yield, it is necessary to be able to extract blood from
the peripheral edge of the placenta. This is then driven towards
the cord. A linear analogy is extracting toothpaste from a
toothpaste tube. Being a thixotropic material, the lack of flow is
not dissimilar to extracting placental blood from the blood vessels
in the placenta. As with the toothpaste analogy, to maximize yield,
it is necessary to apply pressure at a distal region from the
extraction point, and be able to progressively apply pressure
towards the extraction to drive the blood to the cord.
[0018] It will be appreciated that as placentas are almost never
uniform, and will have the cord placed at different locations
within the placenta, the term "central" refers to the extraction
point of the blood within the compartment. That is, the "central"
location is the position of the cord, with the intent being to
drive blood towards the cord for extraction.
[0019] Having pressing members that are capable of applying
peripheral pressure, and may also progressively apply pressure, so
as to direct the blood may be an important aspect of at least one
embodiment of the present invention.
[0020] It will be appreciated that, in some circumstances, maximum
yield may not necessarily be the best strategy. With a possible
window of opportunity of 15 minutes from delivery of the placenta
to clotting or contamination of the blood, being able to extract as
much blood as possible within the available time is important.
Accordingly, if there is a delay in being able to process the
placenta, this window may be dramatically reduced, possibly to the
extent that insufficient time is available to maximize yield, but
only time to extract whatever is available within the reduced time
frame. To this end, in a further embodiment, the pressing members
may also be switchable from a rhythmic, variable pressure
condition, to aggressively apply pressure to the placenta.
[0021] In a further embodiment, the invention may accommodate
asymmetric placentas. It will be appreciated that placentas will
almost certainly never be uniform in shape. Not only will the
placenta be non-uniform, but the position of the cord will vary
also.
[0022] To this end, in a further embodiment, the pressing members
may be subjected to control of a range of parameters, including,
but not limited to: [0023] i) Rate, applied pressure and
displacement of the pressing members; [0024] ii) Selective
operation of individual or groups of pressing members; [0025] iii)
Said selective operation providing the peripheral to central
driving of blood in the veins of the placenta; [0026] iv) Said
selective operation providing different rhythmic cycles for the
movement and pressure application by the pressing members; [0027]
v) Selective operation to identify and accommodate asymmetry of the
placenta and/or position of the cord.
[0028] To this end, and in particular for the initialization
procedure, the device may include a control system, which may
further incorporate adaptive control to adapt operation to varying
shapes, size and other parameters of said placentas.
[0029] In a third aspect, the invention provides a receptacle for
use with a placental blood extraction device, the receptacle
comprising a compartment arranged to receive the placenta; and a
tube extending from the compartment for receiving the umbilical
cord; wherein the receptacle is selectively removable from the
device for receiving the placenta.
[0030] In a fourth aspect, the invention provides a method of
extracting blood from a placenta, comprising the steps of:
encapsulating the placenta with umbilical cord using a receptacle;
inserting a cannula into the umbilical cord; actuating a placenta
blood extracting apparatus with the receptacle loaded therein to
apply a pressure to the placenta; and collecting blood flowing from
the placenta into the cannula.
[0031] The method may further comprise loading the empty receptacle
into a placental blood extracting device prior to
encapsulation.
[0032] The receptacle may comprise a tube extending from a
compartment for receiving the umbilical cord, the encapsulation
step including the step of clipping an end of the umbilical cord
using a weight and allowing the end to fall into the tube.
[0033] The method may further comprise perfusing a medium into the
cord and placenta.
[0034] The medium may include aqueous solutions, anti-coagulant
and/or chemicals which aid content retrieval from the placenta and
cord.
[0035] The actuating step may include the step of applying
vibration to the placenta.
[0036] The method may further comprise applying a negative pressure
to the cannula to facilitate the collection of blood.
[0037] In a fifth aspect, the invention provides an umbilical cord
cutting device comprising: a first and second portion, coupled at
respective ends, in relative rotational engagement about a common
axis, each portion having a slot parallel to the common axis; a
first rotational position aligning the slots of said portions; a
second rotational position misaligning said slots cutting edges on
said respective ends; wherein the device is arranged to receive an
umbilical cord whilst in the first position and on rotation to the
second position the device is arranged to cut the umbilical cord
placed therein.
[0038] The cutting device may further include a pair of clamps each
respectively positioned adjacent to said respective ends, such that
the device is arranged to relatively rotate the first and second
portions from the first position to a third position whereby said
clamps forced into engagement with the cord.
[0039] In a sixth aspect, the invention provides a cannula assembly
comprising: a catheter; a housing mounted to a portion of said
catheter such that a length of catheter projects from said housing;
an introducer in sliding engagement with said housing and arranged
coaxially with said catheter wherein the introducer is movable from
an extended position having a penetration end contiguous with an
end of said catheter and a retracted position such that said
catheter end projects from said penetration end.
[0040] The cannula assembly may further include a selectively
releasable lock arranged to lock the introducer in the retracted
position. The introducer may be a concentric sleeve positioned
externally to the catheter. The retracted position may place the
introducer fully retractable within the housing.
[0041] The cannula assembly may be arranged for penetrating a vein
of an umbilical cord, said catheter having a diameter equal to a
diameter of the cord vein.
[0042] In a seventh aspect, the invention provides a blood bag
assembly comprising: a blood transfer conduit; a blood bag coupled
at a first end of said conduit; a cannula coupled at an opposed end
of said conduit; a blood sampling site for obtaining a blood sample
coupled at a position intermediate said ends; a tapping for an
perfusion system coupled at a position intermediate said ends.
[0043] The blood bag assembly may further include a perfusion
system coupled to the perfusate tapping. The perfusion system may
include a perfusate bag. The perfusion system may include a tapping
for a peristaltic pump. The perfusion system may include a
peristaltic pump coupled to the tapping. The perfusion system may
include a warming device for warming the perfusate bag.
BRIEF DESCRIPTION OF DRAWINGS
[0044] It will be convenient to further describe the present
invention with respect to the accompanying drawings that illustrate
possible arrangements of the invention. Other arrangements of the
invention are possible, and consequently the particularity of the
accompanying drawings is not to be understood as superseding the
generality of the preceding description of the invention.
[0045] FIG. 1 is a perspective view of a placental blood extracting
device, a receptacle and a blood bag, according to a first
embodiment of the invention.
[0046] FIG. 2 is an exploded view of the receptacle of FIG. 1.
[0047] FIG. 3A is a perspective view of a receptacle according to a
second embodiment of the invention and a cannula.
[0048] FIG. 3B is a perspective view of the receptacle of FIG. 3A
loaded with a placenta with the cannula inserted into the umbilical
cord.
[0049] FIGS. 4A and 4B illustrate a process of loading a placenta
into a receptacle.
[0050] FIG. 5A shows a sectional view of a pressure application
device according to a third embodiment of the invention.
[0051] FIGS. 5B and 5C are perspective view and part cutaway view
of an arrangement of the pressing members of the pressure
application device.
[0052] FIGS. 6A and 6B illustrate two further exemplary
constructions of a pressure application device.
[0053] FIG. 7 is a schematic diagram of a placental blood
extracting device.
[0054] FIG. 8 is a flow diagram of a placental blood extracting
process.
[0055] FIGS. 9A and 9B are elevation views of a placenta transfer
system according one embodiment of the present invention.
[0056] FIG. 9C is an elevation view of a perfusion device for the
placenta transfer system of FIG. 9A.
[0057] FIGS. 10A to 100 are sequential views of the in utero
extraction of cord blood according to one embodiment of the present
invention.
[0058] FIGS. 11A and 11B are various views of an umbilical cord
cutter according to one embodiment of the present invention.
[0059] FIGS. 12A to 12D are sequential views of the cutting of an
umbilical cord using device according to the present invention.
[0060] FIGS. 13A to 13C are elevation views of a cannula according
to one embodiment of the present invention.
[0061] FIGS. 14A and 14B are comparison schematic views of blood
extraction using a cannula assembly according to one embodiment of
the present invention compared to a cannula of the prior art.
[0062] FIG. 15 is a schematic view of a blood bag assembly
according to one embodiment of the present invention.
[0063] FIGS. 16A and 16B are schematic views of the blood bag
assembly of FIG. 15.
DETAILED DESCRIPTION OF EMBODIMENTS
[0064] FIG. 1 shows a placental blood extraction device 1, together
with a receptacle 2 having a delivered placenta 4 loaded therein
and a blood bag 3 for using in the placental blood extracting
device 1.
[0065] The placental blood extraction device 1 may further comprise
a placenta receiving bay for receiving a receptacle having a
placenta loaded therein. The placenta 4 may be prepared off-site
with the receptacle 2. The blood extracting process can start once
the placental blood extracting device 1 is loaded with a receptacle
2, which has been prepared with a placenta 4 preloaded. The
placental blood is collected in a blood bag 3.
[0066] An exemplary construction of the receptacle 2 is shown in
FIG. 2. A delivered placenta 4 normally includes a placenta 40 with
an umbilical cord 42 connected. The receptacle 2 may comprise a
compartment 20 into which the placenta 40 is placed, and a tube 22
extending from the compartment for receiving the umbilical cord 42.
The receptacle 2 is selectively removable from the device 1 for
receiving a placenta.
[0067] The receptacle may further include a base, having an
absorbent material therein for collecting excess blood, and so
preventing spillage to maintain a clean and encapsulated collection
process. The base may also be conveniently used to allow the
receptacle to stand alone, aiding the insertion and removal of the
placenta. It will be appreciated that the placenta may remain
within the receptacle for disposal of the entire unit, and so also
aid in maintain a clean and efficient collection and disposal
process. Alternatively, the placenta may be removed for separate
disposal, with the receptacle either cleaned and re-used or
disposed of separately.
[0068] The receptacle 2 may be made of a plurality of components
such as two mating parts as shown in FIG. 2, or a single piece as
shown in FIGS. 3A and 3B. The compartment 20 according to one
embodiment may define a conical or funnel-shaped space of
appropriate size suitable for receiving a placenta 40. The apex of
the compartment 20 is connected to a tube 22 having a length and
cross-sectional area suitable to contain the umbilical cord 42. The
other side of the compartment 20 may be an opening allowing
pressure to be applied onto the placenta 40.
[0069] Optionally, the receptacle 2 may further comprise a cover 24
as shown in FIGS. 3A and 3B. FIG. 3A shows a further embodiment of
the receptacle 2 and a cannula 28 for insertion into the umbilical
cord through the tube 22. The cover 24 allows for the full
encapsulation of the placenta, not merely for the application of
pressure, but also to seal the placenta from sources of
contamination that may affect the extracted blood. Having the
receptacle as a single disposable unit with the placenta sealed
therein, ensures the collection process is clean, efficient and
avoids direct contact with either the extraction device or the
operator.
[0070] The receptacle 2 may be made of disposable material, such
that after each process a user may simply take out the receptacle 2
and replace it with another one, as if replacing a cartridge.
[0071] The compartment 20 may have a circular rim. The compartment
20 and tube 22 may be made of plasticised PVC, so as to be flexible
and relatively soft to avoid damage to the placenta, while the
circular rim may be made of hard PVC to provide rigidity. It will
be appreciated that materials providing similar benefits may be
used without departing from the invention.
[0072] The tube 22 may be lined with one or more rectangular
windows, or recesses 26 to provide users an easy access to the
umbilical cord within it. These windows 26 may be covered by flaps
to prevent unnecessary exposure of the umbilical cord 42 to the
surroundings. Given that umbilical cords vary substantially in
length, and that the cord may also be trimmed prior to the
extraction process, it is important for the receptacle to allow for
this variation by providing multiple cannulation sites. It will be
appreciated that, to avoid contamination by maternal blood, a
region immediately adjacent to the end of the cord is not available
for extracting blood. Nevertheless, by providing multiple
cannulation sites, an optimum placement of the cannula is possible
after the placenta is placed in the receptacle, providing a
convenient and clean setup for the extraction process.
[0073] The tube 22 may be formed of suitable material, shape and/or
dimension to facilitate the gripping of the umbilical cord 42.
Further, the tube 22 may be made of stiff material to prevent it
from being penetrated by a needle or cannula to be inserted into
the umbilical cord 42 so as to prevent a possible "needle stick"
injury to the user by the needle.
[0074] Once a placenta is loaded into the receptacle 2, a cannula
28 may be inserted into the umbilical cord 42 through the windows
26 as shown in FIG. 3B. The cover 24 can be closed. The receptacle
2 is now ready to be loaded into the placental blood extraction
device 1.
[0075] At least a part of the inner surfaces of the receptacle 2
may be lined with absorbent material and this serves to absorb
maternal blood from the placenta 40 and umbilical cord 42.
[0076] The cover 24 may comprise a hard plastic rim and a flexible
membrane which can be made of silicone or other forms of plastic.
After the placenta 4 is inserted into the receptacle 2, the cover
24 can be closed to seal the placenta within the receptacle. The
flexible membrane serves to allow easy transfer of pressure from a
pressure application device 5 to the placenta.
[0077] The receptacle 2 effectively separates the placenta 4 from
the placental blood extraction device 1, and thereby preventing the
placental blood extraction device 1 being contaminated by the
maternal blood or any other fluid on the placenta.
[0078] A process of loading a placenta 40 with umbilical cord 42
into a receptacle 2 is shown in FIGS. 4A and 4B. It may include
clipping an end of the umbilical cord 42 using a weight 44 and
allowing the end to fall into the tube 22.
[0079] After the extraction of the placenta and cord from the womb,
a weighted clamp 44 will replace the hemostat/clamp that is
originally used to clamp the cord during the harvest. It is first
clamped at a position on the cord near the hemostat/clamp but on
the side nearer to the placenta. Subsequently, the placenta and
umbilical cord are inserted into the receptacle, with the cord 42
sliding down the tube 22 and the placenta 40 resting compartment
20. Lastly, the cover 24 is placed onto the compartment 20 to
ensure a complete encapsulation of the placenta and cord. The
weighted umbilical cord clamp 44 may be specially made heavy in
order to allow the umbilical cord 42 to slide easily into the tube
22.
[0080] In a further embodiment, the placental blood collection
device 1 may comprise a pressure application device 5 for applying
pressure to a placenta. FIGS. 5A to 5C are embodiments of a
pressure application device 5.
[0081] As shown in FIG. 5A, the pressure application device 5
comprises a plurality of pressing members 50, 52 for applying
pressure on a plurality of regions of the placenta, wherein the
plurality of pressing members 50, 52 are independently controllable
so as to allow different levels of pressure to be applied onto
different regions of the placenta.
[0082] Optionally, at least one of the pressing members 50, 52 may
be arranged to apply pressure from the bottom side of the placenta,
namely the side of the placenta having umbilical cord extending
there from. Accordingly, in this alternative arrangement, it may be
possible to apply pressure to the placenta as well as the umbilical
as well, optimizing the extraction of blood. The pressure
application device 5 allows the timing of activation of the
pressure members to be controlled so as to apply a desired rhythm
of compression on the placenta.
[0083] In one embodiment, the device may further comprise at least
one pressure sensor for indicating pressure applied on a region of
the placenta. The at least one pressure sensor is attached to at
least one of the pressing members. The device may further comprise
a control system for controlling the pressing members so as to
apply a differential pressure profile on the placenta.
[0084] The control system may include a preset algorithm for a
differential pressure profile, such as in the form of the rhythmic
application of pressure to the placenta. Such algorithm may include
a varying operation of the pressing members such that early in the
collection process, pressure is applied primarily at the peripheral
edges of the placenta, with a central pressure application being of
a lesser degree. As the process continues, the pressure may
increase to increase the blood yield. The control system may be
capable of using a variety of operator selected algorithms.
[0085] The control system may further include a pressure sensor for
providing feedback signal to the control system. The pressure
sensor may be provided on the pressing members. Alternatively, or
in addition to, the system may include displacement sensors.
[0086] Further, the control system, and/or pressure application
device may include a vibratory device to apply vibration to the
placenta to further aid the collection process. Such a vibration
may or may not be part of the applied algorithm. The control system
may be selectively interrupted and/or by-passed by the operator to
allow the operator to directly control the rate, magnitude and
location of the application of pressure.
[0087] The control system may further include an adaptive system.
That is, by analyzing signal input from sensors in communication
with the control system, the control system may adapt control to
meet specific conditions.
[0088] For instance, placentas are generally asymmetric, rather
than a regular elliptical or circular shape. The control system may
include an initialization sequence whereby the shape of the
placenta, and position of the umbilical within the placenta may be
determined. Such an adaptive system may then adjust the
pre-determined arrangement of pressing members to apply pressure
according to the determined periphery and cord location. Such an
adaptation may include activating certain pressing members that are
positioned to contact the placenta, and deactivate other pressing
members that do not. Such an arrangement may further redefine
pressing members as outer, inner and intermediate pressing members
based on the determined shape of the placenta and position of the
cord.
[0089] The control system may be an open loop system, in which
output from sensors are displayed to an operator for their action.
Alternatively, the control system may be closed loop, with the
control system reacting to sensor input. One such example of a
closed loop may include the adaptive system previously
described.
[0090] At least one of the pressing members, or all pressing
members 50, 52, may comprise a resilient portion. Optionally, at
least one of the pressing members, or all pressing members 50, 52,
may be made wholly of resilient material. The resilient portion or
material may prevent potential damage to the placenta during the
blood extraction process. The resilient portion or material may
include any one of a gel pad, air bag, sponge, or any other
suitable material.
[0091] In a further embodiment, the plurality of pressing members
may comprise at least one outer pressing member 52 for applying
pressure onto a peripheral region of the placenta surface. The
device may further comprise an inner pressing member 50 for
applying pressure onto a central region of the placenta
surface.
[0092] While loaded in the receptacle or placental blood extraction
device, the placenta may resemble roughly an ellipsoid or oblate
(flattened) spheroid with a cross-section as shown in FIGS. 6A and
6B. The central region of the placenta surface refers to a region
of the surface opposing and/or adjacent to the point from which the
umbilical cord extends. This corresponds to the top or bottom
surface adjacent to the minor axis. The peripheral region of the
placenta surface is the region further away from the minor
axis.
[0093] The second outer pressing member 52 may be annular, and
comprising a pressure application surface for applying pressure on
the peripheral region the placenta. It may further comprise one or
more intermediate pressing members 54 for applying pressure onto a
region between the central and peripheral regions of the placenta
surface.
[0094] Each of the pressing members 50 and 52 of the pressure
application device 5 may be independently controllable to allow
different levels of pressure to be applied onto different regions
of the placenta. For example, by activating the outer pressing
member 52 for a first period, and subsequently activating the inner
pressing member 50 for a second period, a differential pressure
profile can be applied to the placenta. During the first period,
higher pressure is applied on the peripheral region than the
central region. During the second period, the pressure applied on
the central region increases to expel the blood out of the placenta
through the umbilical cord.
[0095] In one embodiment, there may be a plurality of outer
pressing members 52. Each outer pressing member may have a pressing
surface collectively forming an annular shape. The control system
may be configured to activate the outer pressing member before
activating the mid and/or inner pressing members. The pressing
members may be driven by hydraulic means, gearing systems or
magnetic force.
[0096] Three exemplary types of pressure application device are to
be described detail: full air bag compression system, motorized
compression system and hybrid compression system.
[0097] A full air bag compression system is shown in FIG. 5A to 5C.
It may include a plurality of annular inflatable airbags 50, 52 and
54 of various diameters are fitted into a rigid cylindrical
structure. These airbags are separated from one another by
cylindrical walls 51. During operation, when these air bags are
expanded sequentially from the ones on the outer perimeter to the
inner ones, the placenta is compressed from the edges towards its
centre.
[0098] One of the advantages associated with using a full air bag
system is that the placenta experiences a gentler compression force
as compared to a motorized system involving cams. In addition, it
would be more precise in terms of control of the differential
pressure across the placenta compared to a single silicone membrane
with the dome-shaped cross section.
[0099] In a motorized compression system of FIG. 6A, the pressing
members are in the form of pads 50, 52 connected to cams 56, or
driving members. The cams 56 are capable of reciprocal actuation.
These cams 56 will press the pads 50, 52 against the placenta. In
order to create a differential pressure across the placenta, the
cams 56 can be adjusted to move at different times. For example, if
the outer rings of pads 52 may be lowered before the inner rings,
such that a differential pressure would be created across the
placenta from its perimeter to its center. It will be appreciated
that a control system capable of controlling the motorized
compression system using preset algorithms as previously described
in relation to the air pressure system is also possible. It will be
appreciated that a similar system may be used for applying pressure
to the umbilical cord, either in combination or as an alternative,
so as to extract residual blood. The pressure may be applied to the
cord in a systematic manner from the placenta end of the cord to
the distal end such that the blood is pushed down the cord to the
cannulation site.
[0100] A hybrid compression system of FIG. 6B is structurally
similar to the motorized compression system except that the
pre-inflated airbags 50a and 52a are attached to the pads 50b and
52b, which are in turn connected to the cams 56. This system also
has the advantage of a gentler compressive force of the airbags on
the placenta. In operation, the cams 56 force the pads 50b and 52b,
and the airbags 50a and 52a, downwards onto the placenta and thus
compresses the placenta. The outermost ring of the airbag may be
compressed first, followed by the inner ones so as to create a
differential pressure from its perimeter to its center of the
placenta.
[0101] A schematic diagram of a placental blood extracting device 1
is shown in FIG. 7. The placental blood extraction device may
comprise a main frame 72, a pressure application device 5,
perfusion and collection module 74, and control user interface. The
frame may include a placenta receiving bay for receiving a
receptacle 2 having a placenta therein. The perfusion and
collection module 74 may comprise one or more mechanical pumps 74a,
perfusion means 74b, perfusant solution application means 74c, so
as to apply the perfusion during blood extraction, with the
perfusant solution to disassociate the hematopoietic progenitor
cells in the placenta and thereby assisting the blood extraction.
For example, the perfusant may be an anti-coagulant. The main frame
72 may include a housing with a side opening, through with the
receptacle 2 may be inserted into the placenta receiving bay. The
top of the frame houses the pressure application device. The
pressure application device 5 applies pressure onto the placenta
inside the receptacle 2 through the cover 24.
[0102] A flow diagram of the placental blood extracting process is
shown in FIG. 8. The process includes: encapsulating 80 the
placenta with umbilical cord using a receptacle, inserting 82 a
cannula into the umbilical cord, loading 84 the receptacle into a
placental blood extracting device, actuating 86 the placenta blood
extracting apparatus to apply a pressure to the placenta, and
collecting blood flowing from the placenta into the cannula.
[0103] The placenta is first prepared by encapsulating the placenta
using a receptacle 2. The process may further include a step of
loading the empty receptacle into a placental blood extracting
device prior to encapsulation. The encapsulation may include
clipping an end of the umbilical cord using a weight and allowing
the end to fall into the tube 22. The placenta enclosed in the
compartment 20 and the umbilical cord enclosed in the tube are
exposed and disinfected.
[0104] Subsequently, the umbilical cord is cannulated 84 with the
catheter needle. The process may further include a step of
perfusing a medium into the cord and placenta. The medium could
include aqueous solutions, anti-coagulant and/or chemicals which
aid content retrieval from the placenta and cord. In one
embodiment, the placenta is perfused with a flushing solution
containing anti-coagulant. Perfusion is aided by a mechanical pump.
Upon perfusion, the hematopoietic progenitors present in the
placenta and the cord are dissociated from the surrounding
tissue.
[0105] The receptacle 2 with a placenta therein may then be loaded
into the placenta receiving bay of the placental blood extracting
device 1. In one embodiment, the receptacle may be in sliding
engagement with the device, such that it slides on a rail to
receive the placenta. Further, the receptacle may also be in
rotational engagement, such that the receptacle is inverted to
allow placement of the placenta maternal side first, then reverted
back to the normal position. The receptacle can then be slid back
into the device, following cannulation.
[0106] Lastly, the placenta blood extracting apparatus is actuated
to apply a pressure to the placenta. The cellular extraction is
aided by the application of pressure on the maternal surface of the
placenta via an air bag system. Applied pressure is monitored
through the control user interface 76 so as to prevent the
excessive pressurization. Subsequently, cord blood is drained via
the tubes into sterile blood bags. This actuating step may include
applying vibration to the placenta. The process may further
comprise a step of applying a negative pressure to the cannula to
facilitate the collection of blood.
[0107] In a further embodiment, in order to improve yield, the
device may include an arrangement whereby fluid is injected into
the placenta in order to apply additional pressure for the
extraction of blood. To this end, the fluid path created by such an
arrangement of the device may include: [0108] i) An injection of
fluid through a cannula placed in an umbilical vein, so as to
perfuse fluid through the veins of the placenta; [0109] ii) The
injection of fluid builds pressure in the placenta, which tends the
evacuate blood from the placenta into the cord; [0110] iii) The
evacuated blood is then extracted through a second cannula in the
cord.
[0111] Alternatives to this fluid path include having the injection
cannula and extraction cannula being the same, with a 3 way valve
to accommodate the injection and extraction functions.
[0112] The perfused fluid may include anti-coagulant, saline
solution or other flushing agent.
[0113] FIGS. 9A and 9B shows the placental blood extraction device
according to one embodiment of the present invention, in this case
a placenta transfer system 90. The system 90 includes a receptacle
95, 100 for receiving the placenta 95 and umbilical cord 100 so as
to allow a catheter and conduit, or tube, 105 to extract the cord
blood and deliver to a blood bag located on a blood bag rocker 115.
The system further includes a perfusion system 110 shown in more
detail in FIG. 9C. The system, in this case a perfusion device 110
includes a perfusate bag 125 which fits within the casing of the
device 110. The device 110 further includes a warming device 130
for maintaining the perfusate at a predetermined temperature so as
to ease blood flow. By way of example, the warmer 130 could
maintain the perfusate in a range 35.degree. C. to 40.degree. C. or
more specifically it may warm the perfusate to 37.degree. C. The
warming device may be applied to the bag of perfusant, such as a
bag of anti-coagulant, or may be applied to the conduit, or tubing,
used to transfer the perfusant.
[0114] The device 110 further includes a peristaltic pump 135 so as
to pump the perfusate into the placenta for maintaining a back
pressure as well adding perfusate to the cord blood for ease of
collection. Whilst a peristaltic pump is identified, the skilled
person will appreciate other forms of pressure actuation may be
used, including a syringe pump. To this end, the perfusion may be
stored in said syringe pump replacing the need for a bag.
[0115] During in utero collection, once the baby is delivered, the
umbilical cord is severed and cannulated so as to attach the
collection conduit/tube 105 to the umbilical cord. When the
placenta is delivered it is encapsulated within the receptacle 95,
100 which may be secured to a platform for ex utero extraction.
Pre-warmed perfusate will be perfused into the placenta using the
peristaltic pump 135 and drained out of the placenta through
gravity. From the system 90 the receptacle 95, 100 containing the
placenta may be transferred to a separate machine so as to allow
pressure to be applied to the placenta for further cord blood
extraction. Alternatively, the pressure applicator may be mounted
to the system 90 to apply pressure to the placenta whilst mounted
to the system 90. Once the cord blood collection is complete, the
system 90 can be folded (FIG. 9B) and placed in a more convenient
location having a smaller footprint consistent with the crowded
delivery suite.
[0116] The system is arranged to reduce the turnaround time between
the in utero and ex utero cord blood collection by having the
necessary components integrated into a single system 90.
[0117] FIG. 10A to 10C show a sequential view of the transition
from in utero to ex utero cord blood collection. While the placenta
155 is in the uterus the umbilical cord is placed on an absorbent
receptacle 140. The cord is wiped dry and then cannulated so as to
connect the cord to a blood bag located on a blood bag rocker 150
through a tube 145. After the placenta 155 is delivered it is
placed on the receptacle 140 which then wraps 160 around the
placenta and secured using Velcro. As an alternative to Velcro,
buttons, zips or other forms of binding the receptacle about the
placenta. The placenta and umbilical cord are then placed into the
system as shown in FIG. 9A. In one embodiment, the blood bag rocker
may include sensors for determining the volume of blood collected
in said bag. For instance, a load cell may measure the weight of
the bag, and connected to a display for communicating the weight,
blood volume or % of bag volume to highlight to the healthcare
worker the collected volume, such as to replace the bag or merely
to provide information.
[0118] The system of 9A may be battery powered so as to facilitate
portability. Further the system may be mounted on wheels so as to
further assist in the easy introduction and removal of the system
as required. To achieve the battery powered aspect of the system
the batteries may be rechargeable and so connectable to an
electrical socket or possibly through induction charging.
[0119] The placenta transfer system reduces the critical loss of
time during the transition from in utero to ex utero cord blood
collection and so minimizing the risk of blood clots and overall
improvement of cellular yield. In the embodiment of FIG. 9A the
placenta transfer system may be a compact design to allow the
process to be conducted within the delivery room without the need
of additional manpower transportation or space.
[0120] FIGS. 11A and 11B show a cord cutting device 165 arranged to
receive and cut an umbilical cord 172. The cord cutting device
engages the cord 172 in a manner so that at the time of cutting the
open ends of the cord 172 are enclosed within the device and so
preventing blood splatter. A further consequence of the enclosure
during cutting reduces the risk of injury to healthcare workers by
both cutting the cord within the device and also providing a
secured grip of the cord during the procedure.
[0121] The cord cutting device 165 comprises a first and second
portion 185, 190 which are in relative rotational engagement about
a common axis. The portions 185, 190 are coupled at respective ends
of the portions and have complimentary slots. In the initial
position the slots align and so allow the placement of the cord.
Mounted to the respective portions include cutting edges 175 at the
respective ends. Those areas of the two portions 185, 190 in
proximity to the cord 172 act as a barrier to enclose the cord with
the cutting edges arranged to then cut the cord on a secondary
rotation from the first, initial, position to a second cutting
position.
[0122] Positioned at the respective ends are clamps, initially
placed in an open position. As the cord is placed within the
device, it is consequently placed into the open clamps. On first
rotating the portions 185, 190 to a third position the clamps close
around the cord and lock with sufficient pressure to block blood
flow.
[0123] The placement of the clamps is such that they block blood
loss at the severed ends of the cord following the cord cutting
rotation.
[0124] FIGS. 12A to 12D show a sequential view of the cord cutting
device 165 whereby the umbilical cord 180 is placed within the
aligned slots of the portions of the device 165 in the first
position. The two portions 185, 190 are rotated 195, 191 relative
to each other to a third position so as to close the device around
the cord 180. The two portions 185, 190 are then rotated in an
opposed direction 200, 205 which brings the cutting edges into
contact with the cord and consequently shearing through. In a
further embodiment, the device 165 may include a pair of clamps
187, 192 which as a consequence of the reverse rotation 200, 205
are arranged to clamp the severed ends of the cord 180 so as to
close off the cord preventing further loss of cord blood.
[0125] FIGS. 13A to 13C show a cannula assembly 210 according to
one embodiment of the present invention. The cannula assembly is
applicable in use for most if not all applications of cannula
applications. Certain embodiments of the broad invention, such as
catheter diameter and the singe handed operation also make the
assembly applicable for the extraction of cord blood.
[0126] The assembly 210 comprises a pair of concentric sleeves 225,
230 whereby the outer sleeve, being an introducer 230, is arranged
for penetrating the umbilical cord so as to place the flexible
catheter 225 within the cord vein. The cannula assembly 210 further
includes a slide 220 mounted to the outer penetrative sleeve
(introducer) 230 and is arranged to retract the penetrative sleeve
230 on insertion into the cord vein leaving the flexible catheter
225 in place. The flexible catheter 225 as shown in FIG. 14A is
sized such that the catheter diameter is equal to the diameter of
the cord vein 240 so as to more efficiently extract blood 235 from
the cord vein 240. FIG. 14B shows a prior art catheter 245 which is
typically much smaller than the cord vein 240 and so is not able to
efficiently extract cord blood following insertion.
[0127] The penetrative sleeve 230 or introducer needle being
retractable and lockable in place through use of the slide 220
avoids the disposal of a sharp needle as is the case of prior art
cannulae and so prevent stick injuries to healthcare workers. The
assembly allows the user to cannulate the cord with one hand and
manipulate the cord with the other simultaneously, again unlike the
two handed operation of conventional cannulae. The relative
operational ease further reduces the time for cannulation and so
further prevents the onset of blood clots within the cord as well
as more effectively and efficiently extracting blood.
[0128] Once the punch is made into the cord and the introducer
needle is retracted, the flexible catheter 225 is maneuvered
carefully into the cord vein. Unlike prior art cannulae which have
a stiff catheter the cannula assembly according to this embodiment
uses a soft and flexible catheter designed to fit within the cord
vein and preferably apply pressure to the walls of the vein so as
to further expand the vein for better cord blood extraction.
Ideally, this will capture all the blood flowing through the vein
directly into the catheter and certainly considerably greater
proportion of the blood then would be available through a catheter
of the prior art. Further, the flexible catheter 225 according to
the present invention is more fully insertable into the vein and so
less chance of the catheter 225 from slipping from the vein during
the collection process. FIG. 15 shows a blood bag assembly suitable
for use with the placenta transfer system. The blood bag assembly
250 comprises a blood bag 280 having a cannula 255 at an opposed
end of a tube system. The cannula 255 may be a conventional cannula
or may be a cannula assembly according to one embodiment of the
present invention. The assembly 250 includes a blood sampling site
260 to facilitate the extraction of blood for testing. The blood
bag assembly 250 further includes a coagulant system comprising an
perfusion bag 267 having a spike 265, for selectively mounting the
perfusion bag 267, and a peristaltic pump 270.
[0129] The connection to the tube 252 allows for selective use of
the perfusion whereby in circumstances where perfusion is not
desired or not permitted then the perfusate can be kept away from
the flow of cord blood to the blood bag 280. The peristaltic pump
may be selectively controllable so as to control the volume of
perfusate that is pumped into the cord. A blood sampling site 260
is also included to allow healthcare workers to withdraw a blood
sample for necessary action without interfering with the cord blood
collection process. For example, the blood sampling site may be a
needleless injection site, vacutainer site or other means for
gaining access to the flow of cord blood without having to
interrupt the procedure or blood flow generally.
[0130] FIG. 16A shows the in utero collection process using a cord
blood bag assembly 285. Here the umbilical cord 290 has a cannula
inserted therein during the period prior to delivery of the
placenta. Cord blood is collected for testing 220 through the blood
sampling site 295. Cord blood is then collected 320 in the blood
bag 315. Once the placenta has been delivered the arrangement shown
in FIG. 16B whereby the delivered placenta 317 becomes the source
of cord blood collection 325 into the bag 315. To facilitate the
collection process the blood bag assembly 285 may include a
perfusion bag 300 and peristaltic pump 305 for pumping 330
perfusate into the placenta 317.
* * * * *